Which radiation consists of a helium nucleus with a large mass and positive charge?

Which radiation consists of a helium nucleus with a large mass and positive charge?

• A. Gamma Radiation
• B. Neutron Radiation
• C. Alpha Radiation
• D. Beta Radiation

Answer: (C)

Alpha radiation is defined by being a helium nucleus—two protons and two neutrons—with relatively large mass and a +2 charge. That combination makes it highly ionizing as it passes through matter, but its mass and charge give it very low penetration, so it can be stopped by a sheet of paper or a few centimeters of air. In contrast, gamma radiation is electromagnetic energy with no mass or charge, beta radiation consists of fast electrons or positrons with much less mass and a single unit of charge, and neutron radiation involves uncharged particles that can penetrate more deeply depending on energy. So the description matches alpha radiation.

Alpha radiation is defined by being a helium nucleus—two protons and two neutrons—with relatively large mass and a +2 charge. That combination makes it highly ionizing as it passes through matter, but its mass and charge give it very low penetration, so it can be stopped by a sheet of paper or a few centimeters of air. In contrast, gamma radiation is electromagnetic energy with no mass or charge, beta radiation consists of fast electrons or positrons with much less mass and a single unit of charge, and neutron radiation involves uncharged particles that can penetrate more deeply depending on energy. So the description matches alpha radiation.